Vyacheslav Klyukhin, SINP MSU

1. Vyacheslav Klyukhin, SINP MSU Simulation of magnetic toroids for CMS forward muon detection V. Klyukhin, General Muon mtg, CERN

2. Motivation of the Proposals V. Klyukhin, General Muon mtg, CERN

3. Initial Data • Parameters of the 13 toroids used in the IHEP-JINR Neutrino Detector (IHEP, Protvino): • Outer diameter: 4 m; • Inner square hole: 0.36 × 0.36 m²; • Thickness: 0.22 m (two disks of 0.11 m welded together); • Weight: 25 t; • Material: Russian steel St08; • Number of turns in one coil: 34 of copper with cross-section of 18.5 × 18.5 mm²and an inner hole of 10 mm diameter; • Demineralized water consumption: 14.4 l/min; • Magnetic flux density at the inner radius: 1.9 T; • Magnetic flux density at the outer radius: 1.45 T; • Operational current: 907.6 A at 10.4 V; V. Klyukhin, General Muon mtg, CERN

4. Data Used for Simulation • Outer diameter: 5.2 m; • Inner diameter: 0.4 m; • Thickness: 0.34 or 0.78 m; • Weight: 55.5 or 127.3 t; • Material: vf steel; • Number of turns in one coil: 34 of copper with cross-section of 18.5 × 18.5 mm²; • Coil cross section: 0.038 × 0.330 m²; • Current: 907.6 A at 10.4 V; V. Klyukhin, General Muon mtg, CERN

5. Azimuthal magnetic flux densityat Z=0 m (0.34 m) V. Klyukhin, General Muon mtg, CERN

6. Azimuthal magnetic flux densityat φ=0º (0.34 m) V. Klyukhin, General Muon mtg, CERN

7. Azimuthal magnetic flux densityat φ=45º (0.34 m) V. Klyukhin, General Muon mtg, CERN

8. Azimuthal magnetic flux densityat Z=0 m (0.34 m) V. Klyukhin, General Muon mtg, CERN

9. Radial magnetic flux densityat Z=0 m (0.34 m) V. Klyukhin, General Muon mtg, CERN

10. Radial magnetic flux densityat φ=0º (0.34 m) V. Klyukhin, General Muon mtg, CERN

11. Radial magnetic flux densityat φ=45º (0.34 m) V. Klyukhin, General Muon mtg, CERN

12. Radial magnetic flux densityat Z=0 m (0.34 m) V. Klyukhin, General Muon mtg, CERN

13. Azimuthal magnetic flux densityat Z=0 m (0.78 m) V. Klyukhin, General Muon mtg, CERN

14. Azimuthal magnetic flux densityat φ=0º (0.78 m) V. Klyukhin, General Muon mtg, CERN

15. Azimuthal magnetic flux densityat φ=45º (0.78 m) V. Klyukhin, General Muon mtg, CERN

16. Azimuthal magnetic flux densityat Z=0 m (0.78 m) V. Klyukhin, General Muon mtg, CERN

17. Radial magnetic flux densityat Z=0 m (0.78 m) V. Klyukhin, General Muon mtg, CERN

18. Radial magnetic flux densityat φ=0º (0.78 m) V. Klyukhin, General Muon mtg, CERN

19. Radial magnetic flux densityat φ=45º m (0.78 m) V. Klyukhin, General Muon mtg, CERN

20. Radial magnetic flux densityat Z=0 m (0.78 m) V. Klyukhin, General Muon mtg, CERN

21. Layout of 6 Toroids from the Top(0.78 m) V. Klyukhin, General Muon mtg, CERN

22. Azimuthal magnetic flux densityat Z>0 m (0.78 m) V. Klyukhin, General Muon mtg, CERN

23. Azimuthal magnetic flux densityat Z<0 m (0.78 m) V. Klyukhin, General Muon mtg, CERN

24. Conclusions • The toroids could be located at Z-coordinates of ±11.5, ±12.58, and ±13.66 m (from 11.11 to 14.05 m) in place of the present HF, if it will be moved into the end-cap disks bore; • The pseudorapidity coverage is from 2.39 to 4.02; • The space between the coil of two adjacent toroids is 0.2 m; • The azimuthal magnetic flux density is rather uniform along the beam axis; • The radial magnetic flux density is negligible; • The azimuthal magnetic flux density varies from 1.73 to 2.18 T vs. radius for 0.78 m thick toroids; • The integrals of the azimuthal magnetic flux density vary from 4.17 (η=2.4) to 4.96 (η=4) T·m for 0.78 m thick toroids. V. Klyukhin, General Muon mtg, CERN